When you create a project you can define directories with any number of search paths whose content you want to show in diagrams. For example, you can show entities that reside in the standard Java libraries. Such resources exist for the project, but Together does not include them in the generated HTML documentation for the project.
To show classes or packages from the standard Java libraries in a class diagram:
Open or create a class diagram.
Right-click on the background and choose New > Shortcut. The Shortcuts dialog opens displaying available model elements.
Under the Model Elements tab, expand the libraries node, and navigate to the resource you want to add. Click Add. Repeat until you have added all the resources you want.
Click OK to close the dialog.
TIP: If the resource you are looking for is not shown, it is probably not in the Java build paths defined in Project Properties. You can add resources to the Java build paths at any time by using the Navigator view (NB: Navigator view is not the same as UML Navigator View). Right click on the project name in Navigator view, and select Properties from the context menu. In the dialog that displays, select Java Build Path. Add the appropriate paths to your project by using the different tabs listed on the Java Build Path page.
NB: The new command available from the context menu, New, is disabled for classes that have been added from libraries (or compiled source code) to the diagram.